It never ends.
Third major failure of this 3.5 year old dishwasher.
Second (after the last one I posted here) was a bit simpler, the dishwasher wouldn’t start sometimes and would also sometimes stop intermittently. I could get it to start or resume a stopped wash after a good slam of the door. Replaced the door switch, problem solved.
This time, the third failure, the dishwasher would stop mid-cycle, drain and give the error light sequence: mode lights 1-4 solid yellow, and the power button blinks rapidly. I couldn’t find anything reliable online for the meaning of that light code, with different websites telling me different things. I had a suspicion what this one was; for the last year or so the recirculation pump noise was getting louder and louder, making a kind of chugging sound, almost like a diesel engine bus was idling outside the house.
I figured the pump would need to be replaced at some point anyway so I looked for a replacement on the Indesit parts website:
https://parts.indesit.co.uk/dif16b1u...howCode=true/p
I had to double check what pump I had because it turns out there are multiple versions of the DIF16B1UK, of which use either one of two pumps – from their appearance I’m confident they’re not cross compatible.
Of course the one I needed was the more expensive of the two possibilities… part number was C00731573
I punched that in to Google and ended up buying one for about £85 delivered from ransomspares.co.uk, vs £150 on the Indesit website. The pump that arrived turned out to be from the same OEM as the original as opposed to a 3rd party manufacturer, so that was nice.
This time, access was via the right hand side panel (viewing from the front), for better access I tipped the machine on its left side and also pulled out the bottom sump (the thing which detects leaks – be sure to disconnect the attached float switch, and reconnect when done!)
Pump comes out by twisting it off the heater enclosure, fetid water will gush out, have a rag handy! Make sure to remove the old O-ring and thoroughly clean the O-ring seating surfaces, mine were caked in solidified fat and sand – the kind of stuff that will cause leaks if not removed.
The pump came with two O-rings, of which only one is needed, install that were the old one was and twist the new pump on, making sure the O ring stays where it should be.
Put it back together and test etc. So quiet now!
Doing an autopsy on the old pump – a brushless three phase AC pump with a floating impeller and permanent magnet. The bearings are graphite bushes, one on each side of the magnet. The impeller-side bush also restrains axial thrust, it is secured to a plastic cap which encloses the magnet section of the whole pump.
The cap has small openings to equalise pressure, which I reckon is what caused the pump to fail - small particles making their way past the cap and getting in to and prematurely wearing down the graphite bushings. Both bushes were heavily worn, such that there was about 1-2 mm of radial and axial play! I do wonder how it managed to work for so long in that state!
The new pump has larger openings in the cap, but covered with a fine mesh screen. Good.
As my Google search failed to find any conclusive fix given the symptoms. Here’s the conclusive fix, now on the Internet hopefully for others to find and save some time, and another appliance from the bin maybe.
Bring on the next failure…